We will study the magnetic resonance properties of water protons in frozen protein solutions to identify the basic types of water motions that are present in such systems. "Spin-Spin," "Spin-Lattice," and "Spin-Lattice in the Rotating Frame" relaxation times will be measured. Experiments will continue on the properties of water molecules inside red cells. These experiments include diffusion studies as well as relaxation measurements. Some computer-aided analyses of known protein structures will also be undertaken to examine the role of water in the maintenance of protein conformations. BIBLIOGRAPHIC REFERENCES: A. Zipp, T. L. James, I. D. Kuntz and S. B. Shohet, "Water Proton Magnetic Resonance Studies of Normal and Sickle Erythrocytes, Temperature and Volume Dependence", Biochem. et. Biophys. Acta, 428, 291-303 (1976). P. Kollman, D. Hayes, and I.D. Kuntz, "Electrostatic Properties of Proteins" in Environmental Effects on Molecular Structure, (B. Pullman, Ed.) Reidel, p. 31-39, 1976.